Field of the Invention
The present invention relates to DICOM query/retrieve operations and a special storage method that accelerate the display of DICOM image over a network. More particularly, certain embodiments relate to a web-based DICOM viewer of an international experts co-diagnosis system that intelligently download large DICOM image meta data and pixel data, which are processed before the very first request on these certain objects, in stages by anticipating the possible image content request.
Description of the Related Art
Digital Imaging and Communications in Medicine (DICOM) is a standard for handling, storing, printing, and transmitting information in medical imaging. It includes a file format definition and a network communications protocol. The communication protocol is an application protocol that uses TCP/IP to communicate between systems. DICOM files can be exchanged between two entities that are capable of receiving image and patient data in DICOM format. The National Electrical Manufacturers Association (NEMA) holds the copyright to this standard. It was developed by the DICOM Standards Committee, whose members are also partly members of NEMA.
DICOM enables the integration of scanners, servers, workstations, printers, and network hardware from multiple manufacturers into a Picture Archiving and Communication System (PACS). The different devices come with DICOM conformance statements that clearly state which DICOM classes they support. DICOM has been widely adopted by hospitals and is making inroads in smaller applications like dentists' and doctors' offices.
The contents of the DICOM standard go far beyond a definition of an exchange format for medical image data. DICOM defines data structures for medical images and related data, network oriented services, e.g. image transmission, query of an image archive, print, and RIS-PACS-modality integration formats for storage media exchange, and requirements for conforming devices and programs.
The DICOM network services are based on the client/server concept. In case two DICOM applications are going to exchange information, they must establish a connection and agree on the following parameters: who is client and who is server, which DICOM services are to be used, and in which format data is transmitted (e.g. compressed or uncompressed). Only if both applications agree on a common set of parameters, the connection can and will be established. In addition to the most basic DICOM service “image transmission” there are a number of advanced services, e.g. the DICOM image archive service allows to search images in a PACS archive by certain criteria (e.g. patient, time of creation of the images, modality etc.) and to selectively download images from this archive, the DICOM print service allows to access laser cameras or printers over a network, so that multiple modalities and workstations can share one printer, the DICOM modality work list service allows to automatically download up-to-date work lists including a patient's demographic data from an information system to the modality.
However, the detailed implements of PACS are different from country to country. So far there is no national PACS network yet, much less an international one. Usually medical institutions purchase service and equipment from various venders and make the PACS physically isolated. The disadvantage of this architecture is that, although PACS's could exchange data between each other via DICOM protocol, users still suffer from the latency time in data transmission.